Snap fastener for trimming and like strips



Aug. 17, 1943. H'. J. MURPHY 2,327,328

SNAP FASTENER FOR TRIMMING AND LIKE STRIPS Filed Dec. 9, 1941 Patented1943 SNAP FASTENER TBIMMING AND LIKE RIPS Howard J. Murphy, Greenwood,lMass., asslgnor to United-Carr Fastener Corporation, Cambridge, Mass.,a corporation of Massachusetts Application December 9, 1941, Serial No.422,254

3 Claims.

My invention aims to provide improvements in snap fastener membersparticularly adapted for use in securing a trim piece, such as a moldedstrip, to a support. which may be in the form of a. metal panel.

In the drawing, which illustratesa preferred embodiment of my invention:

Fig. 1 is a plan view of a portion of a trimming installation showingone of my improved fastener members in dotted lines; y

Fig. 2 is a bottom plan view ofthe same por tion of `the installationshown in Fig. l;

Fig. 3 is a section taken on the line 3 3 oi Fig. 2;

Fig. i is a section taken .on the line t-t of Fig. 2;

Fig. 5 is a side elevational view oi my improved fastener member per se;

Fig. 6 is an edge view of the fastener member shown in Fig. 5; and 1-Fig. "l is a section through the trim strip and fastener shown in Fig. 3before it is attached to a supporting panel. 1

While my improved fastener is used with a combination oi elements whichby this time is well known, viz., a trim strip installation,nevertheless I believe my fastener is of much simpler and less expensiveconstruction than any fastener heretofore lmown tor use in a similarinstallation.

a The installation illustrated includes a thin sheet metal supportingpanel l having a studreceiving aperture il, a trim strip, or othersimilar member, il preferably formed from plastic material and having aprojection t on the under side thereof and :my improved snap fastenerformed from a single piece of sheet metal. The snap fastener holds thetwo parts together as clearly illustrated in Fig. 3.

The snap fastener selected for illustration is preferably formed from asprlngy material such as carbon steel heat-treated and has an l-lshapedbase 5 (Figs. l and 2) with an i-l-shaped aperture t. This base ispreferably bowed longitudinally and a pair of gripping ngers 'lintersect the i-l-shaped aperture at the center so that they may gripthe projection t on the part t, as illustrated in Figs. 2 and 3. Due tothe shape of the base t and the aperture 6, these gripping hngers maymove to permit passage of the proiection i, which is preferably ofslightly larger diameter than the space between the opposed edges of thegripping fingers 1 -1. IlI'he fastener also includes a pair of yieldableleg portions 8-8 which extend downwardly from the base and arepreferably continuations of the gripping fingers '|-1, as clearly shownin Fig. 8. The legs 8-8 are bowed longitudinally so that they maycooperate to provide a snap fastener stud means which when entered intothe aperture 2 willcompress and expand to grip the supporting panel I,as clearly illustrated.

In assembling lthe parts of the installation I prefer-first to attachthe fastener to the strip 3 and this accomplished by moving the base ofthe fastener over the projection 4 from the under side of the strip 3.As pressure is applied the projection 4 enters between the opposed edgesof the gripping fingers l-l and they are forced downwardly and apart sothat they may slide over the projection until the fingers 5, Bb, 5 andtd of the H-shapecl base contact the under surface of the part t atwhich time there is a tendency to Hatten the bow-shaped base as pressureis continued. This nattening, together with the natural tendency of thegripping fingers 'l-l to grip into the plastic material, causes theedges of the gripping fingers l--l to bit into .the-material, as clearlyshown in Figs. 3 and '7. Thereafter the part t with the fastenerattached may be put in position relative to the supporting panel i andthe legs t-il of the fastener may be forced through an aperture t bypressing upon the outer surface of the part il. This causes the legs topass through the aperture t in the part Il and as they do they are movedtoward each other until they pass the high points provided by the bowedlegs when they again move away from each other due to their naturaltendency to yield and expand. The legs then grip the material oi thepart i adjacent the aperture t and are held under compression, as willbe seen by a comparison of Figs. 7 and 3. Since the legs are held undersome compression when the installation is complete they also bring somepressure to bear upon the gripping fingers l-l and cause themI to biteallvthe harder into the material of the projection t. Thus the fastenerholds the parts tightly together against any accidental separation,although itis possible to pry the member t, together with the fastenerattached, loose from the supporting panel i.

While I have illustrated and described a preferred embodiment of myinvention I do not wish to be limited thereby, as the scope of myinvention is best dened by the following claims. v

I claim:

,1. A fastener member of the class described formed from a. single pieceof sheet metal and having a normally bowed apertured base having sixyieldabie fingers two of which are presented at the aperture to engage apart to be entered through said aperture and yieldable legs extendingfrom said base and cooperating to provide a. snap fastener means.

2. A fastener member of the class described formed from a single pieceof sheet metal and having an H-shaped base with an H-shaped aperture,said base having six yieldable ngers two of which are presented at theH-shaped aperture to engage a part to be entered through said apertureand yieidable legs extending from said base and cooperating to provide asnap fastener means, and said base being normally bowed to provide'formovement of al1 of the yieldable fingers thereof as and for the purposesdescribed.

3. A snap fastener member formed from a singie p iece oi.' sheet metaland having a bowed yieldable base provided with an aperture to receive aprojection on a part to be fastened. a pair ,of gripping ngers formed insaid base and ex-

